The present invention essentially relates to a sealing device between a casing in which there is a bore and a piston displaceable inside the said bore.
It is known, particularly from French Pat. No. 2,026,459, to dispose a fluid-tight seal in a groove provided on the inside of the casing. However, the said structure has disadvantages, particularly if the groove intended to accommodate the seal is disposed in alignment with the end of the bore, since production of the groove and insertion of the seal are very delicate operations. It can be seen from FIG. 1 of the above-mentioned patent that the groove is made in a cover fixed to the main part of the casing, which therefore entails a higher prime cost.
In order to avoid having to construct the casing in a plurality of parts, the present invention proposes a novel type of structure which permits an easier assembly of the seal in its bore whatever may be the relative position of the seal within the bore.